Multi-layer masonry bed joint subjected to shear: Analytical modelling

摘要

An analytical rheological model capable of describing the loading speed dependent in-plane shear behaviour of a masonry multi-layer bed joint is presented in this paper. Such joints consist of a core soft layer protected by two thin extruded elastomer membranes, which in turn are placed in a bed mortar joint. The extruded elastomer membranes are employed to prevent and/or limit the deterioration of the core soft layer during the cyclic action observed in previous investigations. Joint behaviour is assumed to be linear elastic-perfectly viscoplastic and has been captured by a uniaxial model consisting of three elements: an elastic spring connected in series with the frictional slider and a dashpot (viscous damper). The rheological model is characterized by three material parameters that have been assessed from several series of monotonic and static-cyclic tests on small masonry specimens (triplets). In addition to these three parameters, the contraction of the thickness of multi-layer bed joint due to pre-compression has been considered too. Although model parameters are determined for the multi-layer bed joint with a rubber granulate core soft layer, the parameter space can be extended to the other types of core soft layer once the appropriate test data becomes available. (C) 2019 Elsevier Ltd. All rights reserved.